The red stands for the sweater and the yellow is the pattern. (Both are in half since the sleeve is already sewn.)
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This shows the sleeve cut off from the sweater.
Here is the pattern.
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When I laid the pattern on the sleeve, the sleeve was narrower than the pattern.
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This shows the piece I cut off and the part of the pattern that isn't covered.
I cut the seam of the sleeve down to the level of the point of the crotch on the pattern.
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I discovered that the part of the sleeve that I cut off is the right angle for the rest of the crotch seam.
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I cut off the part that went past the crotch point.
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I traced that piece 4 times (or twice opened up) to come up with a start to a pattern for the gusset.
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I cut it out, rounding it out as I did.
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This shows the actual piece of the sweater sleeve I cut off next to the gusset to show that the gusset isn't quite as long as the piece I cut off. (since this is the one I didn't use as a pattern, it is the original length)
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This shows the placement of the gusset for sewing on. The middle of the long side matches up with the seam on the sweater sleeve.
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I basically just sewed the gusset into the part of the sleeve where I had cut the seam to reach the level of the crotch point.
The girls came over to see what I was doing and Sarah thought it was cool that she could see things in the camera "window". She wanted to take a picture of Emily (who was on the other side of my lap)
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Here is her picture of Emily.
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And her picture of me.
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Then she wanted me to take a picture of her.
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I figured we might as well take a picture of Will, too. He was asleep from a recent trip in the car.